What is the solution for √(4800)=√((80cos ̂)^2+(80sin ̂)^2)?

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Discussion Overview

The discussion revolves around the equation √(4800)=√((80cos ̂)^2+(80sin ̂)^2), focusing on the validity of the equation and the manipulation of trigonometric identities. Participants explore the implications of the equation and how to rearrange it, particularly in relation to the identity sin²(x) + cos²(x) = 1.

Discussion Character

  • Debate/contested

Main Points Raised

  • One participant expresses confusion about the equation and attempts to simplify it, reaching the form 4800/6400=(cos ̂)^2 + (sin ̂)^2.
  • Another participant asserts that the equation is false since sin²(x) + cos²(x) = 1 for all x, and 4800/6400 does not equal 1.
  • A participant acknowledges their earlier mistake and inquires about rearranging a similar equation to solve for the angle, expressing feelings of inadequacy in their understanding.
  • There is a suggestion that if x=(cos ̂)^2 + (sin ̂)^2, then x must equal 1 for the statement to hold true.

Areas of Agreement / Disagreement

Participants do not reach a consensus, as there are conflicting views regarding the validity of the original equation and the implications of the trigonometric identity.

Contextual Notes

The discussion includes assumptions about the values of trigonometric functions and their relationships, which remain unresolved. The participants' interpretations of the equation and its manipulation are based on their individual understandings.

brandy
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my problem is this: √(4800)=√((80cos ̂)^2+(80sin ̂)^2)
pretty simple i no but i still keep making mistakes somewhere.
i can get it down to: 4800/6400=(cos ̂)^2 + (sin ̂)^2
but then i get a little stuck.
by the way ̂=thetre=unkown angle.
good luck
i need it.
 
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It's false... sin2(x) + cos2(x) = 1 for all values of x and 4800/6400 is not equal to 1, thus the equation is simply false.
 
d_leet said:
It's false... sin2(x) + cos2(x) = 1 for all values of x and 4800/6400 is not equal to 1, thus the equation is simply false.

yea i figured that out just before. oops. mybad. but how could you rearange a similar equation so that it equalled thetre.
im not very intelligent if u haven't already noticed.
no wait scratch that. how could u rearrange the equation x=(cos thetre)^2 + (sin thetre)^2
even though my original numbers were incorrect.
 
Last edited:
brandy said:
yea i figured that out just before. oops. mybad. but how could you rearange a similar equation so that it equalled thetre.
im not very intelligent if u haven't already noticed.
no wait scratch that. how could u rearrange the equation x=(cos thetre)^2 + (sin thetre)^2
even though my original numbers were incorrect.

in that situation x must be 1, it cannot have any other value if that is to be a true statement.
 

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